Understanding the JVM's automatic memory management and its structure, including the stack and heap, is crucial for application performance and responsiveness.
An object becomes garbage and eligible for collection only when it is no longer reachable from any stack frame, including references held within other collections.
Garbage collection often requires stop-the-world pauses, and basic non-moving collectors like Mark and Sweep can lead to heap fragmentation over time.
Moving collectors like Mark-Compact and Copy, along with generational collection strategies, combat heap fragmentation and optimize for short-lived objects.
An overview of classic collectors including the single-threaded Serial, multi-threaded Parallel (throughput), and the now-deprecated Concurrent Mark Sweep (CMS).
The G1 collector is the default in modern JVMs, using a region-based approach to provide predictable pause times by focusing on areas with the most garbage.
Specialized collectors like Epsilon (no-op), Shenandoah, and ZGC are designed for specific use cases like ultra-low latency or massive heaps, often at the cost of throughput.
Fully concurrent collectors like ZGC use techniques such as colored pointers and loaded value barriers to move objects and update references without long stop-the-world pauses.
Selecting a garbage collector involves balancing the trade-offs between application throughput, latency from pause times, and overall resource consumption.
27:39Ron Veen
39:56Steve Gordon
27:49Ron Veen
00:18Stefan Baumgartner
30:21Ron Veen
30:36Markus Kett
26:54Vadym Kazulkin
28:07Jonathan Müller
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Jobs that call for the skills explored in this talk.
wunschlösung GmbH
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wunschlösung GmbH
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Amdocs
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